KR100928881B1 - Inspection Contact and Probe Card - Google Patents

Abstract

The electrical properties of the wafer having very fine and narrow pitch electrodes are stably inspected. An inspection contact structure is attached to the lower surface side of the circuit board in the probe card. Sheets each having elastic and convex conductive parts are attached to both sides of the silicon substrate for inspection contact structures. An energization path penetrating in the vertical direction is formed in the silicon substrate, and each sheet conductive portion is in contact with the energization path from up and down. The upper conductive portion is in contact with the connection terminal of the circuit board. At the time of inspecting the electrical characteristics of the wafer, the electrode pads on the wafer are pressed against and in contact with the lower conductive parts. Variations in the height of the electrode pad are absorbed by the lower conductive portion, distortion and warpage are absorbed by the upper conductive portion, and the contact between the conductive portion and the electrode pad is maintained.

Description

CONTACT STRUCTURE FOR INSPECTION, AND PROBE CARD}

The present invention relates to an inspection contact structure and a probe card for contacting an inspected object and inspecting electrical characteristics of the inspected object.

For example, inspection of electrical characteristics of electronic circuits such as ICs and LSIs formed on semiconductor wafers is performed by electrically contacting, for example, a plurality of probe needles arranged on the lower surface of the probe card with each electrode pad of the electronic circuit on the wafer. For this reason, the probe needle should be arranged in accordance with the position of each electrode pad.

However, in recent years, since the miniaturization of electronic circuit patterns has progressed and the electrode pads have become smaller and the gaps between the electrode pads have become narrower, for example, the width dimension is 100 μm or less, the pitch is 180 μm or less, It is desired to form the contact portion. Therefore, it is proposed to use an anisotropic conductive sheet instead of a probe needle (for example, refer patent document 1). The anisotropically conductive sheet protrudes from the one surface of the sheet used as an insulating part, and the some electrically conductive part which has elasticity can form an electrically conductive part with a very fine and narrow pitch.

However, when the anisotropic conductive sheet as described above is simply used, since the conductive portion is fine at a narrow pitch, there is a limit in the dimension of the conductive portion in the height direction, and the amount of displacement in the height direction due to the elasticity of the conductive portion is small. For this reason, for example, the fluctuation of the height of the plurality of electrode pads on the wafer surface cannot be sufficiently absorbed by the elasticity of the conductive portion, and the contact between the conductive portion and the electrode pad becomes unstable in the wafer surface. In addition, since the inclination and distortion of the probe card side caused by the attachment or thermal expansion of the probe card cannot be sufficiently absorbed due to the elasticity of the conductive portion, the contact of the electrode pad in the wafer surface becomes unstable.

Patent Document 1: Japanese Patent Application Laid-Open No. 3-196416 (Japanese Patent No. 3038859)

This invention is made | formed in view of such a point, The inspection contact structure and probe card which can make contact part with respect to a to-be-tested object, such as a wafer, very fine and narrow pitch, and can perform stable contact with a to-be-tested object, Its purpose is to provide.

In order to achieve the above object, the present invention provides a contact structure for inspecting the electrical properties of the inspected object in electrical contact with the inspected object, comprising: a flat substrate and a plurality of elastically attached to both sides of the substrate The sheet | seat comprised from the electrically-conductive part and the insulating part which connects these electroconductive parts mutually is included. The said electroconductive part penetrates the said sheet | seat, and is formed so that it may protrude from both surfaces of a sheet | seat, and the said some electroconductive path which penetrates linearly in the thickness direction is formed so that it may correspond to the said electroconductive part. The electroconductive part of the sheet | seat of both sides of the said board | substrate has contact | connected the edge part of the said electrically conductive path, respectively, so that the said electrically conductive path may be interposed.

According to the present invention, since a sheet having a large number of conductive portions formed in the sheet surface is used, a very fine and narrow pitch contact portion can be realized. And since the sheet | seat adheres to both surfaces of a board | substrate, the electroconductive part of a to-be-tested object side side contact | contacts a to-be-tested object, and the change of the height of a to-be-tested object can be absorbed by the elasticity of the said electroconductive part. In addition, the conductive portion of the sheet opposite to the inspected object is in contact with, for example, the connection terminal of the circuit board that provides an electrical signal for inspection on the probe card side, and the elasticity of the conductive portion causes distortion or inclination of the entire probe card or the circuit board. It can absorb. Therefore, even if a contact part is fine and narrow pitch, contact with a to-be-tested object is stabilized and an electrical property test is performed suitably.

The conductive part of the sheet | seat on both sides of the said board | substrate, and the electricity supply path of the said board | substrate may be arrange | positioned coaxially. In such a case, when the test object is pressed against the conductive portion of one sheet, the force acts on the coaxial through the conductive path from the conductive portions on both sides of the substrate. For this reason, only the opposing right force of the thickness direction acts in a board | substrate, and since a bending moment does not act, breakage of a board | substrate can be prevented. In particular, the effect is great when using a very thin substrate of 1 mm or less.

The sheet is fixed to a frame formed along the outer periphery of the sheet, and may be fixed to the substrate by the frame. In this case, warpage and distortion of the sheet itself can be suppressed, and the sheet can be followed on the surface of the substrate. As a result, contact by the electroconductive part in a sheet surface can be performed uniformly.

The frame may be adhered to the substrate by a silicone adhesive. In such a case, since the frame can be removed from the substrate relatively simply, the sheet can be easily replaced or maintained.

The tip of the conductive portion of the sheet located on the side of the test object may be attached with a thin contacting contact with the test object. In such a case, the contact pressure with respect to the inspected object increases, so that electrical contact with the inspected object can be further stabilized. In addition, since the conductive portion does not directly contact the inspected object, wear of the conductive portion can be prevented.

According to another aspect of the present invention, there is provided a probe card for inspecting an electrical characteristic of an inspected object, the test contact being provided between a circuit board, a circuit board, and the inspected object, and energizing between the inspected object and the circuit board. Contains a structure. The inspection contact structure includes a sheet formed of a flat substrate, a plurality of conductive parts attached to both surfaces of the substrate, and insulating parts connecting the conductive parts with elasticity. The said electroconductive part penetrates the said sheet | seat, and is formed so that it may protrude from both surfaces of a sheet | seat, and the some electroconductive path which penetrates linearly in the thickness direction is formed in the said board | substrate so that the said electroconductive part may correspond. The electroconductive part of the sheet | seat of both sides of the said board | substrate has contact | connected the edge part of the said electrically conductive path, respectively, so that the said electrically conductive path | interval may interpose, and the said test | inspection contact structure is comprised so that attachment and detachment are possible to the said circuit board.

In such a case, the inspection contact structure described above can be attached to and detached from the circuit board, so that the inspection contact structure can be removed and maintenance of the inspection contact structure such as replacement of a sheet can be easily performed.

The inspection contact structure may be adhered to the circuit board by a silicone adhesive. In such a case, the inspection contact structure can be easily removed from the circuit board.

Further, a suction port for adsorbing the substrate of the inspection contact structure may be formed on the circuit board. In such a case, the inspection contact structure can be detachably attached to the circuit board by operating and stopping the suction from the suction port.

According to the present invention, since the inspection of the electrical characteristics of the inspected object is performed stably, the defect of the electronic device can be reliably detected and the quality can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing of the longitudinal cross section which shows the outline of the structure of a probe apparatus.

2 is an explanatory view of a longitudinal section showing the configuration of a contact structure for inspection.

3 is a plan view of the sheet.

4 is an explanatory diagram of a sheet structure.

It is explanatory drawing of the longitudinal cross section of the probe apparatus which shows the state which the electroconductive part and the electrode pad contacted.

6 is a plan view of a silicon substrate when a wiring pattern is formed on an upper surface thereof.

7 is a plan view of a silicon substrate when a wiring pattern is formed on an upper surface thereof.

It is explanatory drawing of the longitudinal cross section of the probe apparatus provided with the piping which has a suction opening.

9 is an explanatory view of a longitudinal section of a contact structure for inspection equipped with a thin contact;

<Description of the code>

1: probe device

2: probe card

10: circuit board

12: Inspection contact structure

20: silicon substrate

21: first sheet

22: second sheet

23: current path

30: Challenge

U: electrode pad

W: wafer

EMBODIMENT OF THE INVENTION Hereinafter, the preferable Example of this invention is described. FIG. 1: is explanatory drawing of the longitudinal cross section which shows the outline of the internal structure of the probe apparatus 1 in which the test | inspection contact structure which concerns on this embodiment is used.

The probe device 1 is provided with, for example, a probe card 2 and a mounting table 3 on which a wafer W as an inspection object is loaded. The probe card 2 holds a circuit board 10 for transmitting an electrical signal to the electrode pad U of the wafer W on the mounting table 3, and the outer periphery of the circuit board 10, for example. Mounted on the holder 11 and the wafer W side of the circuit board 10, and for contacting the electrode pad U on the wafer W to conduct electricity between the circuit board 10 and the electrode pad U. An inspection contact structure 12 is provided.

The circuit board 10 is formed in a substantially disk shape, for example. The lower surface of the circuit board 10 is provided with a plurality of connection terminals 10a for conducting with the inspection contact structure 12.

The inspection contact structure 12 includes, for example, a flat silicon substrate 20, a first sheet 21 attached to an upper surface of the silicon substrate 20, and a second adhered to a lower surface of the silicon substrate 20. The sheet 22 is provided.

The silicon substrate 20 is formed in a thin rectangular flat plate shape of, for example, about 200 μm to 400 μm. As shown in FIG. 2, for example, a plurality of conductive paths 23 penetrating perpendicular to the upper and lower surfaces are formed in the silicon substrate 20. Each of the conductive paths 23 is formed so as to correspond in one-to-one correspondence with the plurality of electrode pads U on the wafer W, for example. The upper connection terminal 23a is formed in the upper end part of the electricity supply path 23, and the lower connection terminal 23b is formed in the lower end part of the electricity supply path 23. As shown in FIG. Further, for example, the processing of the silicon substrate 20 is performed by etching processing using a photolithography technique.

As shown in FIG. 3, the 1st sheet 21 and the 2nd sheet 22 are the rubber | gum sheets which have the elasticity formed in the rectangle in the whole, for example, and the several electrically conductive part 30 arrange | positioned closely in the sheet surface. ) And an insulating portion 31 connecting the conductive portions 30 and 30. As shown in FIG. 2, the plurality of conductive portions 30 are disposed at positions corresponding one-to-one to the electrode pad U of the wafer W and the conduction path 23 of the silicon substrate 20. The insulating part 31 is formed of the polymeric material which has insulation and elasticity, for example. For example, as shown in FIG. 4, the conductive portion 30 is formed by densely filling conductive particles A in a polymer material having insulation and elasticity. Each conductive portion 30 is formed in a rectangular columnar shape that penetrates the sheet and protrudes from both sides of the sheet. By this structure, the electroconductive part 30 is electroconductive in a pressurized state, and has elasticity in the protrusion direction of both surfaces of a sheet | seat. For example, the thickness T of the insulating portion 31 is set at, for example, about 100 μm, and the height H from the sheet surface of the conductive portion 30 is formed at about 30 μm, which is about 0.3 times the thickness of the insulating portion 31. The width D of the conductive portion 30 is, for example, about 85 μm, and the pitch P between the adjacent conductive portions 30 is set to about 180 μm.

As shown in FIG. 3, the outer peripheral portions of the first sheet 21 and the second sheet 22 are fixed to the metal frame 40, for example. The metal frame 40 has a frame shape along the outer periphery of the sheets 21 and 22. As shown in FIG. 2, support portions 41 made of a silicone adhesive are formed on both surfaces of the outer peripheral portion of the silicon substrate 20. The metal frame 40 of the first sheet 21 is fixed to the support portion 41 on the upper surface of the silicon substrate 20. The metal frame 40 of the second sheet 22 is fixed to the support portion 41 of the lower surface of the silicon substrate 20. The height of the support part 41 is adjusted, for example so that each electroconductive part 30 of the sheets 21 and 22 may contact the connection terminal of the electricity supply path 23 of the silicon substrate 20 in a pressurized state. That is, the first sheet 21 is in contact with the upper connection terminal 23a corresponding to each conductive portion 30 in the state fixed to the upper surface side of the silicon substrate 20. In the state where the second sheet 22 is fixed to the lower surface side of the silicon substrate 20, each conductive portion 30 is in contact with the corresponding lower connection terminal 23b. Therefore, the electroconductive part 30 of the 1st sheet 21, the electroconductive part 30 of the 2nd sheet 22, and the electricity supply path 23 are coaxially connected in the vertical direction.

As shown in FIG. 1, the silicon substrate 20 is supported on the lower surface of the circuit board 10 by the support 50 disposed outside the support portion 41 on the upper surface of the silicon substrate 20. The support body 50 is comprised, for example with the adhesive agent made from silicone. The height of the support body 50 is adjusted so that the upper end surface of the electroconductive part 30 of the 1st sheet | seat 21 may contact the connection terminal 10a of the circuit board 10 in the pressed state.

The mounting table 3 is configured to be movable, for example, left and right, and up and down, and can move the loaded wafer W three-dimensionally.

In the probe device 1 configured as described above, the wafer W is loaded at a predetermined position on the mounting table 3, and then the mounting table 3 is moved to show the wafer W as shown in FIG. 5. Each electrode pad U on the top contacts the corresponding respective conductive portion 30 of the second sheet 22. The electrical signal for inspection from the circuit board 10 is transferred to the conductive portion 30 of the first sheet 21, the conductive path 23, and the conductive portion of the second sheet 22 in the contact structure 12 for inspection. It passes through 30 in order and is supplied to the electrode pad U, and the electrical characteristic of the circuit on the wafer W is examined.

In the probe device 1 described in the above embodiment, the sheets 21 and 22 are disposed on both sides of the silicon substrate 20, and the conductive portion 30 of the second sheet 22 is disposed on the electrode pads on the wafer W. As shown in FIG. Since it is made to contact (U), the fine contact part of 100 micrometers or less can be realized by the pitch of 180 micrometers or less. Even if the minute contact portion is realized at such a narrow pitch, for example, the conductive portion 30 of the second sheet 22 on the lower surface side of the silicon substrate 20 has the electrode pad U on the wafer W due to its elasticity. ) Can absorb variations in height. In addition, the conductive portion 30 of the first sheet 21 on the upper side of the silicon substrate 20 can absorb the distortion and the inclination of the circuit board 10 due to its elasticity. Level is maintained. As a result, contact between the electrode pad U in the wafer surface and the conductive portion 30 of the probe card 2 can be performed stably, and the inspection in the wafer surface can be appropriately performed.

In addition, since the conductive portions 30 of the first sheet 21 and the second sheet 22 and the conduction paths 23 of the silicon substrate 20 are arranged in a straight line in the vertical direction, the wafer W When each of the electrode pads U is pressed against the conductive portion 30, only the stresses facing in the thickness direction act on the silicon substrate 20, and no bending moments act on the silicon substrate 20. Breakage can be prevented.

Since the outer circumferences of the first sheet 21 and the second sheet 22 are fixed by the metal frame 40, and the metal frame 40 is attached to the support 41 of the silicon substrate 20, the sheet The sheets 21 and 22 can follow the surface of the silicon substrate 20 while the distortion and warpage of the 21 and 22 itself are prevented. As a result, the contact of the electroconductive part 30 in the sheet | seat 21 and 22 surface can be performed uniformly.

Since the metal frame 40 of the first sheet 21 and the second sheet 22 is fixed to the silicon substrate 20 by a silicone adhesive, the first sheet 21 and the second sheet 22 are It can be easily removed from the silicon substrate 20. For this reason, maintenance and replacement of the 1st sheet 21 and the 2nd sheet 22 can be performed easily.

In addition, since the silicon substrate 20 is fixed to the circuit board 10 by a silicone adhesive, the inspection contact structure 12 is detachable from the circuit board 10, and the inspection contact structure 12 is removed. ) Can be easily removed from the circuit board 10. As a result, maintenance and replacement of the contact structure 12 for inspection can be performed easily.

In the above embodiment, since the silicon substrate 20 is used as the substrate for fixing the sheets 21 and 22, the photolithography technique, for example, at least one of the upper surface or the lower surface of the silicon substrate 20 is used. The predetermined wiring pattern which connects connecting terminals with a metal wire can be formed. For example, as shown in FIG. 6, specific upper connection terminals 23a may be connected to each other by the metal wire 60 on the upper surface of the silicon substrate 20, and as shown in FIG. The connection terminals 23a may be connected to each other by the metal wires 60 so that parallel connection lines are formed. In this case, according to the pattern of the electronic circuit of the wafer W, the plurality of conductive portions 30 to which the upper connection terminals 23a are connected can be used, for example, for inspection of the same electrode. In this case, since one electrode inspection is performed using the plurality of conductive portions 30, the inspection is performed more reliably. In addition, since the connection wiring pattern of the upper connection terminal 23a in the silicon substrate 20 can be made in accordance with the pattern of the electronic circuit, the wiring pattern is relatively simpler than changing the wiring pattern in the circuit board 10. Can be formed and appropriately correspond to the patterns of all electronic circuits. Moreover, you may form the wiring pattern which connects specific lower connection terminal 23b in the lower surface of the silicon substrate 20. As shown in FIG.

In addition, the silicon substrate 20 may be fixed to the circuit board 10 by adsorption. In this case, for example, as shown in FIG. 8, a conduit 71 in which a suction port 70 is opened is provided at a lower surface of the circuit board 10. For example, the conduit 71 passes through the circuit board 10 of the probe card 2 and is connected to, for example, a negative pressure generator 72 provided outside the probe card 2. And when attaching the test | inspection contact structure 12 to the circuit board 10, the negative pressure generator 72 attracts from the suction port 70, and the silicon substrate 20 is attracted by the suction force. It is fixed to). When the inspection contact structure 12 is removed from the circuit board 10, the suction is stopped by the negative pressure generator 72. In this case, the inspection contact structure 12 can be easily removed from the circuit board 10. In addition, the inspection contact structure 12 may be detachably attached to the circuit board 10 by, for example, magnetic force.

As described above, when the inspection contact structure 12 is detachable from the circuit board 10, the inspection contact structure 12 can be easily removed from the probe card 2, and this can be replaced. . As described above, since the conductive portion 30 of the first sheet 21 can absorb the distortion and the inclination of the circuit board 10 due to its elasticity, for example, warpage or the like is caused in the circuit board 10. Even if it is, a stable contact state can be obtained. Therefore, the inspection contact structure 12 can be replaced without fine adjustment even in a normal working environment away from the prober. In addition, a contactor directly contacting the wafer W (conductive portion in this embodiment) is fixed to the probe card 2 (directly the circuit board 10) in the silicon substrate 20 portion of the inspection contact structure 12 for inspection. 30 can be formed in a desired plane. That is, it can be made parallel to the probe card 2, without fine-tuning.

A contactor for contacting the electrode pad U of the wafer W may be attached to the tip of the conductive portion 30 of the second sheet 22 described in the above embodiment. In this case, for example, as shown in FIG. 9, a plurality of contacts 80 having a sharp tip end are arranged to correspond to the respective conductive portions 30 and held in the holder 81. The contact 80 is formed of a conductive metal, for example. The holder 81 is formed in a flat plate shape, for example, and is formed of an insulating material. The outer circumferential portion of the holder 81 is supported on the lower surface of the silicon substrate 20 by, for example, the support member 82, and the upper surface of the contactor 80 is in contact with the lower surface of the conductive portion 30 in a pressurized state. It is. When inspecting the electrical characteristics of the wafer W circuit, the electrode pad U on the wafer W is pressed against the tip of the contact 80, and the electrical signal of the circuit board 10 passes through the contact 80. It is supplied to the pad U. In this case, the contact pressure between the contactor 80 and the electrode pad U increases, so that the contact can be stabilized more. In addition, since the conductive portion 30 does not directly contact the electrode pad U, wear or damage of the conductive portion 30 can be prevented.

As mentioned above, although an example of the Example of this invention was described, this invention is not limited to this example, A various form can be employ | adopted. For example, the shape, number and arrangement of the conductive portions 30 described in the above embodiments can be appropriately selected. In addition, the board | substrate which comprises the test | inspection contact structure 12 is not limited to a silicon substrate, For example, the organic substance substrate which can be etched, a silicon dioxide substrate, a glass substrate, etc. may be sufficient. Moreover, this invention can be applied also when the test object is other board | substrates, such as FPD (flat panel display) other than the wafer W, and the mask reticle for photomasks.

Industrial Applicability The present invention is useful for stably inspecting electrical characteristics of an inspected part having a fine narrow pitch.

Claims (8)

An inspection contact structure for electrically contacting a test object and inspecting electrical characteristics of the test object. A flat board, A sheet attached to both surfaces of the substrate, the sheet having a plurality of elastic conductive portions and an insulating portion connecting the conductive portions to each other; The conductive portion is formed to penetrate the sheet and protrude from both sides of the sheet, The said board | substrate is formed with the some electrification path which penetrates linearly in the thickness direction so that the said electroconductive part may correspond, The conductive portions of the sheets on both sides of the substrate are in contact with the ends of the corresponding conductive paths, with the conductive paths interposed therebetween. And the sheet is fixed to a frame formed along the outer periphery of the sheet, and is fixed to the substrate by the frame. The method of claim 1, The contact structure for inspection that the conductive part of the sheet | seat of both sides of the said board | substrate and the electricity supply path of the said board | substrate are arrange | positioned coaxially. delete The method of claim 1, And the frame is bonded to the substrate by an adhesive made of silicon. The method of claim 1, A contact structure for inspection, wherein a contactor having a thin end contacting the inspected object is attached to a distal end portion of the conductive portion of the sheet located on the inspected object side; A probe card for inspecting the electrical characteristics of a subject, Circuit board, It is provided between a circuit board and a to-be-tested object, Comprising: The test | inspection contact structure for energizing between the to-be-tested object and the said circuit board, The inspection contact structure, A flat board, A sheet attached to both sides of the flat substrate, the sheet having a plurality of elastic conductive portions and an insulating portion connecting the conductive portions to each other; The conductive portion is formed to penetrate the sheet and protrude from both sides of the sheet, The said board | substrate-shaped board | substrate is formed with the some electrically conductive path | pass which penetrates linearly in the thickness direction, corresponding to the said electroconductive part, The conductive portions of the sheet on both sides of the flat substrate are in contact with the ends of the corresponding conductive paths, with the conductive paths interposed therebetween. The sheet is fixed to a frame formed along an outer periphery of the sheet, and is fixed to the substrate by the frame, And the inspection contact structure is detachable from the circuit board. The method of claim 6, The said inspection contact structure is a probe card adhere | attached on the said circuit board with the adhesive agent made from silicone. The method of claim 6, And a suction port for adsorbing the flat substrate of the inspection contact structure on the circuit board.

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